new v7 classic/cafe final drive ratio (too revvy!)

[chrisk]

Hi, I’ve just test ridden a v7 and found that it’s revving pretty high at 70 mph. I made it about 4000 revs at 70 mph. Can someone confirm how much it’s revving at 70mph?

So I’m thinking of changing the final drive ratio. There is a 35/8=4.375 advertised on the www.mgcycle.com website, does anyone know what sort or reduction this will give. I’ve seen standard listed as 4.825.

Any more ideas, details of stockists of final drives? Is changing the drive a DIY job?
Chris

 

[draidt]

That's about right, no need to change anything the 750 is best between 3500 and 5K and above, you can't hurt it. New to Guzzi's ? Takes time to adjust to the rev band on all of them 750,1100,1200.

You will still get about 50 Mpg at 70 mph

 

[Holt]

I'd say a modern smallblock would rev about 5000 rpm at 70mph/112kmh ? My memory may fail, but I'm quite sure that 4000 rpm is equal to 90 kmh (56 mph) , which is a very unpleasant speed on my Breva - it's the unsweet spot spot on.:mrgreen:
Unfortunately it's also the "basic speed" limit here. :dry:
Concerning the number of revv's it's just OK. You may be used to some kind of cruiserthing, if 4000/70 is a high number to you.

 

[john zibell]

4,000 RPM at 70 MPH. That is just the way my 1990 MKV and 1100 Breva are geared. Are you sure you weren't turning about 5,000? Anyway, as stated above, those RPMs are pretty much optimum for the engines. In time it will feel just right.

 

[chrisk]

Hi all, update - test rode a v7c again, 70 mph = 4400 rpm, 80 mph = 5100 rpm.

Anyway, I love the little f*ker, so I'll be buying one over the next couple of weeks. I just wish it either had another gear or would be doing about 4500 rpm at 80mph.

I was talking to the parts bloke at a guzzi dealer who said that the drive box from a nevada has the ratios 31/8=3,875, which might fit, but that he couldn't tell for sure and that the only way to tell would be to try it. Any idea on this one ?

Chris

 

[Holt]

Your mechanic may quote an older Nevada; these are the transmission figures for the present one:

Cambio 5 marce
Valore rapporti cambio

1^ 11/26 = 1:2,3636
2^ 14/23 = 1:1,6429
3^ 18/23 = 1:1,2778
4^ 18/19 = 1:1,0556
5^ 25/22 = 1:0,88
Lubrificazione Forzata con pompa a lobi
Trasmissione primaria Ad ingranaggi rapporto: 16/21 = 1:1,3125
Trasmissione finale A cardano rapporto: 8/33 = 1:4,825
Frizione Monodisco a secco con parastrappi

- and for the V7C:

Cambio: 5 marce
Valore rapporti cambio:
1° 11/26 = 1 : 2,3636
2° 14/23 = 1 : 1,6429
3° 18/23 = 1 : 1,2778
4° 18/19 = 1 : 1,0556
5° 20/18 = 1 : 0,9
Lubrificazione: forzata con pompa a lobi - capacità circuito: 1,78 kg
Trasmissione primaria: ad ingranaggi, rapporto: 16/21=1 : 1,3125
Trasmissione finale: a cardano, rapporto 8/33=1 : 4,825
Frizione:
monodisco a secco con parastrappi

Pretty much the same, as I can see. :dry:

Haven't tried, but I'd guess the transmissions can be swapped right over, but do check the parts catalogue. If the #-numbers are the same, they can.

 

[chrisk]

hi, whilst we're on the subject, 33/8 = 4.125 not 4.825... I don;t get it...

 

[chrisk]

Hi all, John Z was right, it does feel right. Basically the bikes gearing is spot on. For fast a-roads 70-80 is 4-5k, which is about as fast as it's right for, and 90 is okay for the occasional blast of for overtakes on the motorways. You can't really sit at anything over 80 on the motorway, without a fairing anyway, well not for long ...

So guzzi are right, I'm wrong...bow...

Chris

 

[GuzziHero]

I dont know how valid my smallblock experience is here, but it sounds identical to my old '79 V50/II. 5000RPM (just nicely uncomfortably vibratey!) was bang on 80mph. It'd hit 90 and hold, but didn't feel too nice. Highest I got was an indicated 108 downhill, tailwind, passing a Goldwing so I was probably getting a bit of a tow

Guzzi don't seem to change ratios often. Part of why I think the Griso has too many gears is that 4000rpm on the '95 Cali is 80mph. 4000rpm on the Griso in top is... 80mph. The Griso's extra gear is factored in somewhere in the lower gears which I feel is exactly the wrong place for it.

 

[Colin Beechey]

I have a Breva 750 (same engine as the V7) and a Honda CX 500. My Breva feels very unrevvy compared to the Honda which has the same power (around 50BHP) but is revving much higher, 7000rpm at 80mph!! So the Breva feels very lazy and unstressed in comparison and is a delight to ride.

 

[Penis Rotor]

All of the alternative ratios listed on the MG Cycle site are, to the best of my knowledge, for the big block bikes, older Tontis and the like.

The smallblocks all use the same final drive ratio, with the possible exception of the NTX and such like but I honestly believe they are the same. There is bound to be a smallblock nutter who will correct me if I'm wrong.

Admittedly I try to avoid smallblocks if I can but certainly with all the *Earlier* as in up to about 2000 models the gearing changes were all done by the primaries in the gearbox, not by the final drive.

Last thing. It's a Guzzi smallblock. Even more than the bigblocks they like to REV. If you wnat a Harley clone? Buy one. Don't try and turn a Guzzi smallblock into one.

Pete

 

[GuzziHero]

I need to make a correction. The Griso 11 is 5000rpm at 80mph in top, not 4000. Since I've seen it pop over 130mph, thats a taaaaaall gear.

Guzzi's do rev to what seems at first to be unnaturally high speed. If the V7 is anything like the V50, uncomfortably so at motorway speeds.